function initWebSocket(url) {
    var websocket = null;

//判断当前浏览器是否支持WebSocket
    if ('WebSocket' in window) {
        websocket = new WebSocket(url);
    } else {
        alert('Not support websocket');
        return websocket;
    }

//连接发生错误的回调方法
    websocket.onerror = function () {
        setMessageInnerHTML("error");
    };

//连接成功建立的回调方法
    websocket.onopen = function (event) {
        console.log(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>");
    }

//接收到消息的回调方法
    websocket.onmessage = function (event) {
        setMessageInnerHTML(event.data);
        alert(event.data);
    }

//连接关闭的回调方法
    websocket.onclose = function () {
        setMessageInnerHTML("close");
    }

//监听窗口关闭事件，当窗口关闭时，主动去关闭websocket连接，防止连接还没断开就关闭窗口，server端会抛异常。
    window.onbeforeunload = function () {
        websocket.close();
    }

//将消息显示在网页上
    function setMessageInnerHTML(innerHTML) {
        // document.getElementById('msg-div').innerHTML += innerHTML + '<br/>';
        console.log(innerHTML);
    }

//关闭连接
    function closeWebSocket() {
        websocket.close();
    }

//发送消息
    function send() {
        // var message = document.getElementById('text').value;
        // websocket.send(message);
    }

    return websocket;
}
